When Ben Wurst began working with Ospreys in 2004, he noticed an unusual element in their nests: plastic. Since then, it’s become something of an obsession for him. Now, as an Osprey expert at the Conserve Wildlife Foundation of New Jersey, Wurst spends much of his time responding to reports of Osprey nests laced with trash and climbing ladders to remove the manmade materials. But after years of this work, he has noticed a troubling trend: Osprey nests are filled with more dangerous plastic garbage than ever before.

Human waste routinely finds its way into birds’ nests, and it is especially common with Ospreys. The birds use a huge variety of materials to build their nests, including sticks, bark, sod, grass, vines and algae. Plastic items mimic the appearance of many of these natural building supplies, and Osprey find plastic trash mixed in with their natural nesting materials in beach wrack lines, making it hard for them to distinguish what’s what, Wurst says. “While Osprey see plastic as a useful resource for them to build their nests from, they don’t see the potential danger.”

By 2012, Wurst realized the problem was worsening, so he began removing the trash and collecting it to raise awareness of the issue. Wurst’s Osprey nest-trash collection includes all kinds of plastic items, including unusual finds such as plastic shovels, flags, and polyester hats. But he believes the most dangerous and deadly items are the most common ones he finds in nests: plastic ribbon from balloons and monofilament fishing line. “Trash like monofilament, ribbon, and string can easily entangle a foot, leg, or wing of an adult or young Osprey,” he says. In addition, “single use plastic bags or other plastic sheeting can choke or smother them.”

The uptick in nest plastic observed by Wurst and others is worrisome, but it also makes sense when you consider that more plastic trash is being produced and improperly disposed of around the world today than ever before, according to the latest research on plastic production, consumption, and disposal. By analyzing reams of global data on plastic manufacturing, researchers behind a recent report found that about 8.3 billion metric tons of virgin plastic has been produced since the 1950s, mostly to manufacture consumer products. Out of that, six-point-three billion metric went unrecycled—with most of it ending up in landfills and the environment.

To prevent further environmental damage and mitigate risk to wildlife like Osprey in the long term, experts agree that already manufactured plastic must be reused and recycled rather replaced with new plastic materials. As the authors of the recent plastic report warn, without a proper plan in place to responsibly dispose of end-of-life plastics, billions of metric tons of plastic will continue to accumulate in the natural environment.

While sweeping changes are necessary to battle plastic pollution, Wurst also likes to remind people that they can contribute on an individual level. “We encourage people to make ‘Osprey-friendly’ choices in their daily lives,” like using reusable shopping bags instead of plastic, properly disposing and recycling trash, never releasing balloons, and cleaning up litter, especially plastic, he says. “If we all do a little then it can make a big difference for protecting our environment and Ospreys.”

In the meantime, Wurst will be out there, responding to calls and climbing ladders, helping Ospreys one trashy nest at a time.